Benign paroxysmal positional vertigo is the most common vestibular disorder. Patients with this problem complain of vertigo elicited by up/down head rotations. It can be disorienting, somewhat disabling, and can interfere with sleep and driving skills. In the previous funding period we tested the overall effectiveness of several standard treatments and some common variations, but did not examine the differences among diagnostic subgroups. In this funding period, we will test the effectiveness of passive repositioning maneuvers and repositioning exercises for canalithiasis vs. cupulolithiasis. Since lateral canal involvement is a common variant, we will study the prevalence and response to treatment of people posterior canal plus lateral canal involvement. We have evidence from the previous funding period that suggests this population may have an unusually high number of individuals with co-morbid rhinosinusitis, so we will study this issue more closely. Therefore, this study will have the following specific aims: 1. Determine the effectiveness of Epley's canalith repositioning maneuver and Semont's libertory maneuver in treating canalithiasis and cupulolithiasis, the two possible subcategories of BPPV. 2. Determine if use of the passive repositioning maneuvers in combination with one week of the Brandt & Daroff exercise at home is more effective for treating P-BPPV than the maneuvers alone. 3. Determine the influence of lateral canal BPPV. A) Determine the prevalence of L-BPPV in P-BPPV patients. B) In P-BPPV patients who also have L-BPPV, determine if treatment with the Semont maneuver followed by log rolling is as effective as use of just the Semont maneuver. 4. Determine the influence of rhinosinusitis. A) Determine the prevalence of rhinosinusitis in patients with BPPV. B) Determine if the presence of rhinosinusitis affects severity of symptoms or response to treatment.